Burglar alarm



June' 14", 1927.

. T. R. CASTLES BURGLAR ALARM 'Filed April 5. 1926 /775 #WOR/Vir Patented June 14, 1927.

THOMAS R. CASTLES, OF PORTLAND, OREGON.

BURGLAR ALARM.

Application filed April 5, 1926. Serial No. 99,839.

This invention .relates generally to protecting devices to be used against burglars and other intruders, and particularly to a special form of alarm which acts as a coinbined window or door stop and alarm.

The main object of this invention is to provide an exceedingly simple and eiiicient Ylevice for sounding an alarm when an attempt is made to open a door or window after the device is set in position thereon.

The second object is to so construct the device that it can be operated by either a door or window.

The third object is to construct an alarm that is positive in its operation and not liable to get out of order.

These, and other objects, will become more apparent from the specification following as illustrated in the accompanying drawing, in which Figure 1 is a front elevation of the device showing it being operated by the partial opening of a door. Figure 2 is a front elevation of same showing it applied to a window. with portions broken away in section. IIiigure 8 is a side elevation.

Similar numbers of reference refer to th same parts throughout the views.

Referring in detail to the drawing, the de vice consists of a somewhat triangular or wedge-shaped sheet metal frame composed nf a front 10, a back 11, side 12 and end 13 having a curved guard 14 extending around a bell 15 mounted on the side 12. Between thc front 10 and the back 11 is placed a side 16 which covers the Smaller end of the frame or point of the wedge. A rubber pad 17 .is secured to the outer side of the member 16 for the purpose of preventing the dcvice from slipping on wood or marring its surface. Teeth 18 are provided at the floor# engaging end of the member 13, which will hold vthe device in place on a rug or carpet.`

To the hinged end 19 `is attached a flat arm 20 extending under the bell 15 and having ears 21 on the sides thereof adapted to frictionally engage the front 1() and the back 11. Between the front 10 and the back 11 are mounted the plates 22 which are spaced apart and attached to the members 10 and 11 by means of the bolts 23. Be'- tween the plates 22 are mounted the. elements of an alarm train or spring motor, which includes an escape wheel 24, an escape lever 25, a gear 26 and pinion 27 for driving the escape wheel 24 and a spiral spring 28 on the wheel shaft 29. A hammer 8() is mounted on the hammer arm 31 which, in turn, is mounted on the pivot 32 which carries the escape lever 25. A key 33 is pro. vided for winding the spring 28.

In order to illustrate the operation of the device as applied to a door there is shown the position of the door 84, floor 35 and carpet 36 in their relation to the device.

To illustrate the operation of the alarm as appli-ed to a window there isindicated a window sash 37, sash cord 88 and the run- Y way 39 of a window frame.

The operation kof the device is as follows: Vhen desiring to attach the alarm to a door the door is closed and the hinged end of the alarm is placed under the door, but withouttouching'it (or at least only slightly). The hinged arm is now lifted to lock the alarm and the spring is wound tight. Any ing movement of the door 34 forces the member 2O downwardly and releases the hammer 80, and of course sounds the alarm and also prevents any further opening ofthe door, due to the wedging action of the device.

When using in connection with a. window, the sash cord 38 is pulled away from the window frame and the device slipped into place, behind the cord, as shown in Figure 2. The function of the curved guard 14 1s to hold the sash cord 38 away from the bell 15. Obviously, a slight raise on the window will releasel the alarm by pressing the member 20 against the side .12, and also prevent any further raising of the window.

I am aware that many forms of burglar alarms have been constructed in the past; it is not my intention therefore to cover such devices broadly, but only within the limits described in the following claim:

I claim:

A burglar alarm having, in combination,` a vwedge-shaped frame having one side hinged at the point thereof having mea-ns for frictionally holding same in an Outward openposition; n bell on said frame; a hammer :l'or striking said bell; a Spring motor for actuating said hummer, said hinged side intereeptng the movement of said hammer when held in. an Outward position, and adapted to release said hummer when said hinged side is moved toward said frame;

and a guard on said frame adapted to permit same to be placed behind a sash eord Without having said eord engage said hinged l0 side unless a window is moved toward said frame.

THOMAS R. CASTLES. 

